Fix glyph width calculation and Remove extra spaces (#722)

Author: LonelyMidoriya

wcag-validation/src/main/java/org/verapdf/gf/model/factory/chunks/ChunkParser.java

@@ -832,15 +832,13 @@ private List<Double> parseTextShowArgument(COSBase argument, StringBuilder unico
 						double shift = - obj.getReal() / 1000 *
 								graphicsState.getTextState().getTextFontSize() *
 								graphicsState.getTextState().getHorizontalScaling();
-						if (-obj.getReal() >= TextChunkUtils.TEXT_CHUNK_SPACE_RATIO && StaticStorages.getIsAddSpacesBetweenTextPieces()) {
-							textPieces.add(new TextPieces.TextPiece(" ", textPieces.getCurrentX(),
-									textPieces.getCurrentX() + shift));
-						} else {
-							textPieces.shiftCurrentX(shift);
-						}
+                        textPieces.shiftCurrentX(shift);
 					}
 				}
 			}
+            double threshold = graphicsState.getTextState().getTextFontSize() * TextChunkUtils.TEXT_LINE_SPACE_RATIO;
+            textPieces.addSpaces(threshold);
+
 			unicodeValue.append(textPieces.getValue());
 			if (!textPieces.isEmpty()) {
 				textMatrix.concatenate(Matrix.getTranslateInstance(textPieces.getStartX(), 0));
@@ -867,17 +865,18 @@ private void parseString(COSString string, StringBuilder unicodeValue, TextPiece
 							" in font" + graphicsState.getTextState().getTextFont().getName());
 					width = 0.0;
 				}
-				double shift = (width *
-								graphicsState.getTextState().getTextFontSize() / 1000 +
-								graphicsState.getTextState().getCharacterSpacing() + (code == 32 ?
+				double shift = (graphicsState.getTextState().getCharacterSpacing() + (code == 32 ?
 								graphicsState.getTextState().getWordSpacing() : 0)) *
 								graphicsState.getTextState().getHorizontalScaling();
-				String value = graphicsState.getTextState().getTextFont().toUnicode(code);
+                width = width *
+                        graphicsState.getTextState().getTextFontSize() / 1000 *
+                        graphicsState.getTextState().getHorizontalScaling();
+                String value = graphicsState.getTextState().getTextFont().toUnicode(code);
 				if (symbolEnds != null) {
 					if (symbolEnds.isEmpty()) {
-						TextChunksHelper.updateSymbolEnds(symbolEnds, shift, 0, value != null ? value.length() : 0);
+						TextChunksHelper.updateSymbolEnds(symbolEnds, shift + width, 0, value != null ? value.length() : 0);
 					} else {
-						TextChunksHelper.updateSymbolEnds(symbolEnds, shift, symbolEnds.get(symbolEnds.size() - 1),
+						TextChunksHelper.updateSymbolEnds(symbolEnds, shift + width, symbolEnds.get(symbolEnds.size() - 1),
 						                                  value != null ? value.length() : 0);
 					}
 				}
@@ -892,7 +891,8 @@ private void parseString(COSString string, StringBuilder unicodeValue, TextPiece
 					unicodeValue.append(result);
 				} else {
 					textPieces.add(new TextPieces.TextPiece(result, textPieces.getCurrentX(),
-					                                        textPieces.getCurrentX() + shift));
+					                                        textPieces.getCurrentX() + width));
+                    textPieces.shiftCurrentX(shift);
 				}
 			}
 		} catch (IOException e) {

wcag-validation/src/main/java/org/verapdf/gf/model/factory/chunks/TextPieces.java

@@ -77,6 +77,26 @@ public List<Double> getSymbolEnds() {
 		return ends;
 	}
 
+    public void addSpaces(double threshold) {
+        List<TextPiece> spaces = new ArrayList<>();
+        Iterator<TextPiece> validation = textPieces.iterator();
+        if (!validation.hasNext()) {
+            return;
+        }
+        TextPiece prev = validation.next();
+        double previousEnd = prev.getEndX();
+
+        while (validation.hasNext()) {
+            TextPiece piece = validation.next();
+            double currentStart = piece.getStartX();
+            if (currentStart - previousEnd > threshold) {
+                spaces.add(new TextPieces.TextPiece(" ", previousEnd, currentStart));
+            }
+            previousEnd = piece.getEndX();
+        }
+        textPieces.addAll(spaces);
+    }
+
 	public static class TextPiece {
 		private final String value;
 		private final double startX;
@@ -91,6 +111,10 @@ public TextPiece(String value, double startX, double endX) {
 		public double getEndX() {
 			return endX;
 		}
+
+        public double getStartX() {
+            return startX;
+        }
 	}
 
 	public static class TextPieceComparator implements Comparator<TextPiece> {